This specification relates generally to providing search results in response to search queries.
A search engine or personal assistant device receives queries, for example, from one or more users and returns query results responsive to the queries. For example, the search engine or personal assistant device can identify documents responsive to a query, generate query results with information about the documents, and provide the query results in response to the query. Other types of query results, for example, direct answers to questions posed by the user, or a summary of information responsive to the user's query, can also be provided. The usefulness of a search engine or personal assistant device can depend on its ability to provide satisfactory query results.